The present invention relates to an electronic device attached with a terminal.
In addition to a normal chip component that is solely directly mounted on a board, as shown in Patent Document 1 for example, a chip component attached with a metal terminal is proposed as an electronic device, such as a ceramic capacitor.
It is reported that the electronic device attached with a metal terminal after being mounted has a reduction effect on a deformation stress that travels from a board to a chip component and a protection effect on a chip component from impacts or so. Thus, the electronic device attached with a metal terminal is used in a field where durability, reliability, and the like are required.
In conventional electronic devices with a metal terminal, however, a terminal electrode of a chip component and a metal terminal are joined by only a solder, and there is a problem with the joint. For example, the soldering operation needs to be conducted while the terminal electrode of the chip component and the metal terminal are being positioned. In particular, when a plurality of chip components is soldered to a pair of metal terminals, this operation is complicated, and the joint reliability may decrease.
When the entire end surface of the terminal electrode of the chip component is soldered with the metal terminal, the connection strength between the metal terminal and the terminal electrode is improved, but the metal terminal is hard to be deformed elastically. In this case, vibrations easily travel from the chip component to a board or so, and a so-called acoustic noise phenomenon may be generated. For use in a high temperature environment or an environment of large temperature variation, the connection between the chip component and the metal terminal may be released due to difference in thermal expansion coefficient between the chip component and the metal terminal.
Incidentally, an electronic device connecting a chip component and a metal terminal by an engagement arm is also proposed. In this structure, a prevention effect on acoustic noise phenomenon is expected to be demonstrated. To further increase a connection strength between the chip component and the metal terminal, it is considered in this structure that a metal terminal and an end surface of a terminal electrode of a chip component are connected by solder. In this case, however, the prevention effect on acoustic noise phenomenon may be weakened.    Patent Document 1: JP2000235932 (A)